This invention is directed to a safety device in the form of a door stop which is adapted to be positioned generally in an opening in the floor adjacent the door. Other mountings are, however, possible, for instance, the door stop may be mounted in the wall or ceiling adjacent the door and, accordingly, be more appropriately hand operated. In any event, the door stop of the present invention represents an improved construction over those presently available in that it is reliable, simple to operate, and of low cost construction. The device is furthermore easily mountable in its operable position flush with the surface adjacent the door and involving formation of but a single mounting opening or end. The device also is easily removable as a unit and formed from components which may be individually replaced.
Prior art publications of which the present applicant is aware and which the present device forms ann improvement thereover include the following U.S. Pat. Nos. 628,795 to Harkness patented July 11, 1899; 1,036,098 to Harkness patented Aug. 20, 1912; 1,866,233 to Tarrant patented July 5, 1932; 1,940,084 to Grasso patented Dec. 19, 1933; 3,330,585 to Pollin patented July 11, 1967; and West German Pat. No. 1,584,058 patented Mar. 26, 1970.
Although applicant is not aware of whether or not the devices described in the various patents have been produced or commercially available, they appear to present drawbacks or limitations which are overcome by the present device. Such advantages as well as those previously indicated as desirable for door stops of this present type are accomplished by the provision of a door stop adapted for positioning in an opening in a surface adjacent a movable door and adapted to move from a retracted position wherein said door may move therepast to an extended position wherein said door movement is prevented, said door stop comprising an outer cylindrical housing having upper and lower ends, said upper end being open and adapted for positioning substantially flush with said surface, an inner member with an outer cylindrical surface adapted to telescopically slide in free rotational relation to the inner surface of said outer cylinder between said retracted and extended positions, said inner member having an enlarged annular lower end adapted to slidably contact said outer cylinder inner surface so as to function as lower guide means, and said outer cylinder open upper end including means for slidably contacting said inner member and acting as upper guide means, spring means for continually urging said member upwardly to its extended position wherein it projects above said outer cylinder upper end so as to contact and block said movement of said door, positioning means inwardly extending from said outer cylinder at an intermediate location between the ends thereof, said inner member including outwardly biased detent means adapted to extend from the outer surface thereof at an intermediate point thereof and engage undersurface portions of said positioning means such that said member is retained in said retracted position, said member downwardly movable against the action of said spring means by pressure applied to the top thereof such that sudden release thereof enables said detent means to move past said positioning means to its extended position wherein said enlarged lower end of said member positively contacts said positioning means so as to prevent further upward movement of said member by said spring.
Other objects, features and advantages of the invention shall become apparent as the description thereof proceeds when considered in connection with the accompanying illustrative drawing.